Alkali Silica Reaction in Concrete Using a New Portland Cement Made from Municipal Waste Incinerator Ash

在这项研究中得到的结果如下：（1）测量膨胀由于在砂浆中含有破碎的瓶状玻璃骨料的碱硅酸盐反应是远远大于用Pyrex玻璃骨料制成的砂浆。（2）与瓶玻璃粉末相比，氧化锂玻璃粉末在抑制碱硅酸反应方面是显著有效的。添加氧化锂玻璃粉末时膨胀的大幅降低似乎源自玻璃粉末作为火山灰的性质和从玻璃中释放的锂。（3）在高碱水泥砂浆中掺入20%的粉煤灰，即使在玻璃砂骨料中，也能完全抑制ASR的膨胀。（4）在纵向约束下产生的膨胀压力与自由膨胀成正比，但15%煅烧燧石砂浆（Na_2O_e为2.0和2.5%）表现出高膨胀，但膨胀压力较低。富碱砂浆的这种异常行为似乎是由于富碱ASR凝胶的产生。（5）膨胀压力试验结果表明，即使含有高碱含量ASR凝胶的混凝土在实验室膨胀试验中表现出很大的膨胀，在约束条件下混凝土构件中由膨胀压力引起的二次应力引起的损伤可能并不显著。（6）将锂离子浸入具有反应性骨料的砂浆中可以在浸入0.5N LiOH溶液后不久阻止砂浆的膨胀。（7）在密封在乙烯基袋中较长时间预固化的砂浆中，砂浆的膨胀较早开始下降。（8）大多数ASR凝胶中的碱离水泥浆体和活性骨料颗粒之间的界面不远，似乎被来自外部溶液的锂离子所取代。

The results obtained in this study are as follows ;(1)Measured expansions due to the alkali silica reaction in mortars containing a crushed bottle glass aggregate were far greater than in mortars made with the Pyrex glass aggregate.(2)The lithia glass powder was conspicuously effective in the suppression of the alkali silica reaction as compared with the bottle glass powder. Great reduction in expansion with the addition of the lithia glass powder appear to be derived from the nature of the glass powder as a pozzolan and the lithium released from the glass.(3)The addition of as much as 20% fly ash completely suppressed ASR expansion even in high alkali cement mortars with the crushed bottle glass aggregate.(4)The expansive pressure generated under longitudinal restraint was in proportion to free expansion except that the 15% calcined flint-containing mortars with a high Na2Oe of 2.0 and 2.5% showed high expansions, but low expansive pressures. This exceptional behavior of the alkali-rich mortars appears to be due to the production of alkali-rich ASR gels.(5)The results obtained in the expansive pressure experiment suggest that, even if concretes containing ASR gels with a high alkali content exhibit great expansions in laboratory expansion tests, damages due to secondary stresses induced by the expansive pressure in concrete members under restraint may not be significant.(6)The intrusion of lithium ions into mortar with a reactive aggregate could arrest the expansion of mortars shortly after immersion in 0.5 N LiOH solution.(7)Expansion of mortars started decreasing earlier in mortars pre-cured in sealed in vinyl sacks for longer periods.(8)The alkalis in most ASR gels not far from interfaces between the cement paste and reactive aggregate particles appear to be replaced by the lithium ions supplied from the external solution